One limitation from the original Princeton architecture is the single path for both data and instructions to memory. This is known as the "von Neumann (a)   ".

The major invention in the second generation of computers was the switch from unreliable vacuum tubes to (a)   .

(a)   memory is made from many tiny ring shaped magnets woven together.

" (a)   on a chip" designs move most of a computer's components onto a single integrated circuit chip.